ICP Analysis Research Articles

Restoration of the Performance of Membranes Fouled and Wetted in a Pilot-scale Membrane Distillation Process

Objectives : The fouling and wetting of membranes in membrane distillation processes can significantly reduce membrane performance, thereby affecting overall process efficiency. The purpose of this study is to develop methods for restoring the performance of membranes used in a membrane distillation pilot plant operated in the Middle East by testing and optimizing various cleaning methods. This aims to maintain the long-term performance and improve the operational efficiency of the pilot plant through the reuse of restored membranes.Methods : To analyze the main fouling substances on the hollow fiber membranes collected from a module operated in a pilot plant, FTIR, XRD, and SEM analysis techniques were employed. A lab-scale module was fabricated using the collected membranes, and cleaning methods were applied. Citric acid was used for cleaning to restore membrane performance, which was evaluated by measuring water permeability and conductivity before and after cleaning.Results and Discussion : FTIR and XRD analyses revealed that the main fouling substances on the membranes used in the pilot plant were NaCl, CaCO<sub>3</sub>, and CaSO<sub>4</sub>. SEM and ICP analyses confirmed that the membranes near the feed inlet of the module experienced severer fouling compared to those near the outlet. The cleaning method involving pump circulation after inducing artificial wetting was found to be the most effective for restoring membrane performance. Notably, when a high concentration of citric acid was used, almost all fouling substances on the membrane surface were removed, restoring membrane performance to nearly its original state.Conclusion : The cleaning method involving artificial wetting followed by pump circulation was determined to be the optimal method for successfully restoring the performance of membranes fouled and wetted in membrane distillation processes.

Synthesis of a wide range of biphenyl derivatives and symmetrical sulfides, using SnFe2O4@SiO2@P-Pd MNPs as a novel, efficient, green, and reusable catalyst

We have introduced the SnFe2O4@SiO2@P-Pd catalyst for the one-pot synthesis of biphenyl derivatives and symmetrical sulfides. For this purpose, SnFe2O4 nanoparticles were modified with Phenylalanine. The synthesized catalyst underwent characterization through BET, FT-IR, SEM, XRD, ICP, TGA, VSM, and EDX analyses. This novel approach offers the advantages of a recyclable heterogeneous catalyst, which can be easily separated from the reaction mixture using an external magnet, along with shorter reaction times, high product yields, and cost-effective, environmentally friendly conditions. The SnFe2O4@SiO2@P-Pd catalyst can be reused for up to five cycles without significant loss of catalytic activity. The results indicate that SnFe2O4@SiO2@P-Pd is an effective hybrid catalyst for synthesizing biphenyl derivatives and symmetrical sulfides.

Solid-to-gas phase transition kinetics of diverse potassium occurrence forms during biomass pellet combustion: Time-resolved detection and multi-step modeling

The solid-to-gas phase transition of potassium during biomass combustion significantly impacts ash-related issues in bioenergy systems, affecting operational efficiency and equipment longevity. However, the specific mechanisms and kinetics of this transition process remain inadequately understood. This work investigates the time-resolved transition of solid-phase potassium to the gas phase during the combustion of rice husk and wheat straw pellets, combining experimental measurements with theoretical modeling. Tunable diode laser absorption spectroscopy (TDLAS) was employed to measure atomic potassium concentrations 15 mm above burning pellets tray, where gas-phase equilibrium is approached. Key combustion characteristics including thermogravimetric profiles, spectral radiation, and temperature were simultaneously monitored. A novel multi-step model was developed to describe the transition of different forms of solid-phase potassium (organic, exchangeable, and inorganic) to the gas phase. This model integrates TDLAS measurements, observed combustion characteristics, and biomass physicochemical properties. Thermodynamic equilibrium calculations were used to estimate the atomic potassium fraction from total gaseous potassium. The results showed that the solid-to-gas phase transition of organic potassium synchronizes with volatiles release. In contrast, the maximum emission rates of inorganic and exchangeable potassium occurred at the onset of char combustion. The developed model agrees well with the online detection experiments and were further validated by offline ICP analysis of residual ash. While not directly simulating gas-solid interface reactions near the particle surface, this work lays groundwork for future multi-scale modeling of particle-laden flows and reactor-scale phenomena in biomass combustion systems.

Catalytic hydrothermal reaction of biomass and its application in blast furnace injection: Physicochemical, conversion mechanism, combustion behavior

This study employs a combination of experimental research and computational fluid dynamics (CFD) simulation to evaluate the optimal conditions for catalytic hydrothermal carbonization suitable for blast furnace injection. Through FTIR spectroscopy, Raman spectroscopy, ICP analysis, and combustion kinetics analysis, the physical and chemical properties of the hydrochar were determined. Subsequently, these properties along with kinetic parameters were applied to an improved CFD model to compare the flow patterns and combustion performance of hydrochar with PCI coal in blast furnaces. The results indicate that the optimal HTC conditions are identified at 300 °C with FeCl3 catalysis, yielding hydrochar (HTC-300-FeCl3) characterized by a calorific value of 32.10 MJ/kg, 98 % K element removal, and enhanced carbonaceous structure ordering. This is attributed to the addition of FeCl3 effectively enhances the generation of hydroxyl radicals in the aqueous phase and promotes deoxygenation and hydrogenation reactions in the solid phase, improving the quality of hydrochars. In addition, CFD model shows that the HTC-300 FeCl3 exhibits a higher burnout (86.2 %) and average gas temperature (2383.1 K) compared to PCI coal, indicating its greater potential as a PCI coal substitute in BF injection.

Efficient conversion of xylose and corncob to furfural using a novel carbon-based solid acid derived from black liquor lignin-tin complexes

The novel carbon-based solid acid catalyst was prepared by carbonizing the mixture of metal salts and black liquor, followed by sulfonating. The physicochemical properties of the catalysts were characterized by SEM, FTIR, BET, NH3-TPD, Py-IR, XPS, ICP, and elemental analysis. The catalytic ability of the catalyst was explored by converting xylose and corncob to furfural via a one-step process. The effects of solvent types and water contents, catalyst dosage, substrate concentration, reaction temperature, and reaction time on furfural yield were evaluated. 93.4 % of furfural yield was achieved using 200 mg xylose at 170 °C for 120 min with 150 mg catalysts. Moreover, the furfural yields of 82.5 % were obtained from corncob. This work provides a promising strategy for synthesizing carbon-based solid acid catalysts from pulp waste black-liquid resources, which has a potential application for producing furfural from hemicellulose.

Aluminium bioavailability and toxicity disrupted chloroplast structure and inhibited inorganic carbon utilization and nutrient uptake in Vallisneria natans at acidic and alkaline pH

Vallisneria natans, as submerged aquatic plants, face significant threats from aluminium (Al) toxicity. While the effects of Al at low pH on terrestrial plants have been extensively studied, there is a lack of research on the impacts of both low and high pH on chloroplast ultrastructure and nutrient uptake in submerged plants. This research is important as it aims to fill this gap by exposing the leaves of Vallisneria natans to 100 μM Al at varying pH levels (4.5, 5.5, 7.5, and 9.5) for 48 hours. The results showed that inorganic carbon (CT), CO2, and HCO3 content increased at extreme pH levels (4.5 and 9.5), suggesting decreased inorganic carbon utilization under Al stress. Additionally, photosystem II efficiency and electron transport rate were significantly reduced at extreme pH levels, highlighting the sensitivity of V. natans to Al. Chlorophyll a and total chlorophyll content were significantly lower at pH 4.5 compared to pH 7.5. Chloroplast structural disruptions were evident at extreme pH levels coupled with Al exposure, whereas minimal injury was observed at pH 5.5 and 7.5. The study also noted vacuole enlargement, altered plasma membrane permeability, and hematoxylin staining, indicating Al accumulation in leaves. ICP analysis revealed increased Al content at extreme pH levels, underscoring heightened Al bioavailability and toxicity. Significant reductions in macro and micronutrient content (P, Mg, K, Fe, Zn, B, Mn) were observed, likely due to Al-induced root and cell damage and altered nutrient uptake. These findings emphasize the complex interplay between Al exposure, pH fluctuations, and their cascading effects on the physiology and elemental composition of Vallisneria natans, highlighting the need for further research and environmental management strategies.

The characteristics of V, Sc, Cr and Ni within the Cambrian terrigenous-carbonate deposits found in the Syuldyukar kimberlite field (Western Yakutia)

The investigation of the Syuldyukar kimberlite field, located within the Yakut diamond-bearing province, involved approximately 4,000 X-ray fluorescence (XFA) analyses and 150 inductively coupled plasma atomic emission spectroscopy (ICP AES) analyses on the host sedimentary rocks of the Upper Cambrian Holomolokha formation in proximity to the kimberlite bodies. The results indicated a disruption in the correlation ratios when compared to background concentrations, while subclark levels of vanadium (V), scandium (Sc), chromium (Cr), nickel (Ni), and other elements remained consistent. The elements were divided into three categories: typomorphic elements for kimberlites (Cr, Ni, Co), elements associated with carbonatites (barium (Ba), strontium (Sr), neodymium (Nd), zirconium (Zr)), and elements characteristic of basalts (V, Sc, zinc (Zn)). High positive correlation coefficients were established for the specified elements in the background concentrations. However, ICP analyses indicated significant decreases in the correlation between elements from different groups in the near-kimberlite space at the Syuldyukar site. X-ray diffraction (XRD) studies showed that in the compression areas, the correlation ratios of various elements were inconsistent when compared to the stretching areas. The analysis of the XRF and ICP data reveled that the average elemental concentrations in the background and near-tube space were nearly identical, except for some unusual hurricane values, with variations showing only slight changes. The positive correlation of several elements likely reflects background geological processes, including sedimentation in a marine basin and subsequent transformations such as hypergenesis, diagenesis, and catagenesis. The significant decrease in correlation coefficients, even with background concentrations remaining stable, is likely due to the redistribution of elements in the fluid resulting from phreatomagmatic explosions linked to the intrusion of kimberlites. Aqueous chloride fluids were observed to most actively redistribute elements in areas experiencing local tectonic compression. The identified changes in the correlation ratios of background elemental concentrations in sedimentary rocks containing kimberlite could act as a new indicator for locating hidden diamond-bearing kimberlites.

Biosorption of methylene blue by bone meal: experimental and modeling with machine learning and full factorial design

Sorption technologies have been proposed for the treatment of water containing methylene blue (MB), a toxic and persistent pollutant. Despite its environmental risks, the role of process variables in MB removal has not been fully explored through experimental design. The objective of this study is to assess the potential of bone meal powder (BMP), an underexplored agricultural byproduct, as an affordable adsorbent for the removal of MB from water. BMP was subjected to a series of analytical characterization techniques, and its adsorption capacity was evaluated through a comprehensive factorial design, which investigated the effects of biosorbent dosage, solution pH, and initial MB concentration. The study revealed that the highest adsorption level was 14.49 mg g−1, attained under the following conditions: 1 g L−1 BMP, pH 11, and 100 mg L−1 MB. The adsorption equilibrium was reached within 60 min, with a measured capacity (qexp) of 18 mg g−1. Theoretical adsorption isotherms indicated a capacity of 63 mg g−1, which aligned well with the Langmuir model. To predict adsorption outcomes, machine learning models were applied, with multiple linear regression performing best. Optimization of decision trees and neural networks improved accuracy but risked overfitting. FT-IR, XRD, and ICP analyses indicated ion exchange as a significant mechanism of adsorption. In desorption studies, H2SO4 was the most effective agent, achieving 68.72% desorption efficiency. BMP exhibited optimal recyclability for up to four cycles before efficiency declined.

The synthesis of Fe3O4@SiO2-NNO-CuII nanocatalyst and investigation of its application in the synthesis of imidazo[1,2-a]pyridines

In this study, a tridentate Schiff base ligand obtained from the condensation of salicylaldehyde and 3-amino-1,2,4 triazole was covalently immobilized on the surface of 3-chloro-trimethoxysilane-functionalized magnetic nanoparticles. This nitrogen and oxygen-rich compound provides donor arms for the coordination of copper ions. The prepared nanocatalyst (Fe3O4@SiO2-NNO-CuII) has been characterized by various techniques including FT-IR, EDX, SEM, VSM, XRD and ICP analysis and used as an efficient recyclable catalyst for the synthesis of imidazo[1,2-a]pydidines. Imidazo[1,2-a]pyridine products were obtained through the coupling reaction of substituted benzaldehydes, 2-aminopyridine derivatives and phenylacetylene under solvent-free conditions in high yields and short reaction times.

Effect of additional Al sources on early-age strength of fly ash-based geopolymer containing calcium carbide residue and Glauber’s salt as activators

Alkali-activated materials are more environmentally friendly than cementitious composites and are used in the construction and building sector. However, their intrinsic low early strength under ambient temperatures hinders their practical applicability. More research is needed on the possibilities of increasing early strength at ambient temperatures. In this study, aluminum sulfate (AS) was used as an additional aluminum source to improve the early-age properties of fly ash (FA)-based geopolymers incorporating calcium carbide residue (CCR) and Glauber’s salt (GS) as activators. XRD, TG, SEM, ICP and isothermal calorimetry analyses were carried out to characterize the phase composition, microstructure and hydration process of the prepared materials. The results showed that the 1d strength of AS1-CCR10 was increased by 260.7 % compared with the control material, and the effect on the late strength was negligible. The relative content of AFt increased by 2.97 %, creating a more compact microstructure. During the extraction process, insufficient dissolved Al3+ in the composite led to a decrease in initial strength. In the hydration process, the induction period of AS1-CCR10 was advanced by 40.92 % and that of t50 was advanced by 57.74 %, which accelerated the early reaction rate. However, the Krstulovic-Dabic model could not accurately describe the initial stage of the hydration reaction of composite materials. This study is helpful to broaden the utilization of geopolymer composites and provide a theoretical basis for the preparation and reaction mechanism of alkali-activated materials.

Corrosion evaluation of austenitic stainless steels in Li2CO3-K2CO3 eutectic salt for thermal energy storage

Molten carbonate salt is one of the promising candidates for high-temperature thermal energy storage tailored towards advanced pumped-thermal energy storage and next generation concentrated solar power technologies. However, severe corrosion of structural materials exposed to molten carbonate salts poses one of the most pivotal threats in terms of limiting their large-scale application at ever-escalating temperatures. Here, we elaborate the compatibility of three commercial austenitic stainless steels specifically SS310, SS316L and Incoloy 625 with Li2CO3-K2CO3 (28–72 wt%) eutectic salt. The corrosion behavior and corrosion mechanism of Fe-Cr (SS316L), Fe-Cr-Ni (SS310) and nickel-based (In625) alloys at 600 °C in air were also investigated. It revealed that SS310 exhibited better corrosion resistance compared to SS316 and In625, with weight loss of 23.8 mg/cm2 and corrosion rate of 522 μm/year after 500 h of exposure at 600 °C. This implies that higher Ni content of the alloy may not necessarily improve the corrosion resistance, it is associated with the basicity of the molten and the solubility of Ni salt in the melt. ICP analysis indicated that the salts exposed to SS310 and In625 at the same exposure time both had nearly 11 times more Ni than that exposed to SS316. Precisely, it is related to the behavior of the Cr-enriched zones formed in the corrosion layers of different alloys. The corrosion mechanism of SS310 specimens in molten carbonate can be generally divided into the following steps: (i) selective oxidation of the metal elements and lithiation reactions of the metal oxides to generate a passivation scale, (ii) an ever-growing middle transition scale consisted of mixed metal oxides and lithium-containing compounds, (iii) cracking and peeling off of the corrosion scale.

Mesoporous Silica with an Alveolar Construction Obtained by Eco-Friendly Treatment of Rice Husks.

The high silicon content in rice plant waste, specifically rice husks, makes this waste by-product attractive for the extraction and valorization of silicon oxide, which is widely used as an inert support in catalysis, drug delivery and molecular sieving. The procedures currently used for the treatment of plant biomass make extensive use of mineral acids (HCl, H2SO4, HNO3), which, besides them being potential environmental pollutants, reduce the yield and worsen the chemical-physical properties of the product. In this study, an evaluation of the easy treatment of rice husks by benchmarking different, more eco-friendly carboxylic acids in order to obtain a mesoporous SiO2 with an alveolar structure and a relatively high surface area and pore volume (300-420 m2/g, 0.37-0.46 cm3/g) is presented. The obtained mesoporous silicas are characterized by worm-like pores with a narrow size distribution and a maximum in the range of 3.4-3.5 nm. The mesoporous structure of the obtained materials was also confirmed by TEM. The complete removal of the organic part of the rice husks in the final materials was evidenced by thermogravimetric analysis. The high purity of the obtained mesoporous silica was detected using ICP analysis (98.8 wt. %). The structure peculiarities of the obtained mesoporous silicas were also characterized by solid-state NMR and ATR-FTIR spectroscopies. The morphology of the mesoporous silica was investigated by SEM.

High turnover and selective Bin-Pd-NCs catalyst for nitro group non-hydrogen reductions in H2O under air conditions: A sustainable and recyclable route to aromatic amines

A green synthesis of anilines by the non-hydrogen reduction of nitro compounds is described. The reaction and post-treatment purification processes can produce high-purity target products without the use of organic solvents. The key to success lies in the synergistic action of two reaction mechanisms. The hydrogen transfer system is significantly accelerated by the presence of binaphthyl-palladium nanoclusters, which permits the catalyzed selective transfer hydrogenation under air conditions, providing a general preparation of aromatic amines in good-to-high yields with excellent chemoselectivities. Benefitting from the heterogeneous manner in water, successful recycling of the catalysts was further achieved with high reaction efficiency maintained. Meanwhile, the ICP analysis results show that the residual palladium content in the target product was below 5 ppm.

Comparison between synthetic and natural clinoptilolites for adsorptive removal of metal ions

The present work evaluated the removal performances of Ni2+, Cd2+, Sr2+, Mn2+, and Fe3+ from an aqueous solution using a comparison between synthetic clinoptilolite (SCP) and natural CP (NCP). Unlike previous demonstrations that treated each metal ion individually, these five metal ions and the used adsorbents were combined in a single treatment and explored via various characterizations, such as XRD patterns, SEM images, N2 sorption isotherms, ICP, and AAS analysis. The results revealed that the capacities of SCP at pH 3.0–8.0 and 25–75 °C were nearly 20 times higher than those of NCP, showing 2000, 1720, 1875, 1510, and 22 mg g−1, for Ni2+, Fe3+, Cd2+, Mn2+, and Sr2, respectively. The reason is mostly attributed to its purity and perfect crystal lattice. The kinetic behaviors in both cases indicated that the pseudo-2nd-order model provided a better description. Their adsorption behaviors exhibited a better fit with the Freundlich models on the removal of Ni2+, Cd2+, and Mn2+, the Langmuir equation on the removal of Fe3+, and both Freundlich and Langmuir on the removal of Sr2+, respectively. The thermodynamic findings indicated that the SCP was used to be faster, more spontaneous, and had a better favorable adsorption performance than the NCP. Additionally, five times recyclability and different stability tests further supported the dominant adsorbent nature of using SCP as an adsorbent.

Recovery of antimony from acidic and alkaline leaching solution of low-grade antimony ore by electrowinning process

With regards to the global continuous growth in consumption of base metals such as antimony (Sb), mining companies are currently looking to improve the productivity and extraction of Sb from low grade ore in order to economically process it. With this aim, in this study, an efficient protocol was developed to recover metallic Sb from the low grade Fe3Si2O5(OH)4. Sb3O6(OH). Sb2O3 ore of the Sefid-Abe mine in Zahedan province, Iran, utilizing selective acidic or alkaline leaching followed by Sb electrowinning. A process was developed to recover antimony from an Sb2O3 ore source, using selective acidic or alkaline leaching followed by antimony electrowinning. Sb could be leached with an efficiency of 85 % using 5 M NaOH and 87 % using 5 M hydrochloric acid/5 M sulfuric acid as the digestion solution at 80 °C for 8 h. The electrowinning process plays a significant role in recovery of highly pure Sb metal. Relying on this approach, a high deposition rate and current efficiency have been generated at a deposition potential 2 V at 30 °C (80 °C for alkaline medium). This was achieved by using anode electrode made of graphite and cathode electrode made of steel (two steel electrodes were used for alkaline electrowinning). Additionally, for acidic electrowinning, exploitation of Sb from the electrolyte solution was achieved by applying a current of 0.1 A, resulting in the highest yield equal to 89 %. On the other hand, for alkaline electrowinning, the highest efficiency corresponds to the current intensity of 0.5 A, which resulted in 97 % Sb extraction from the electrolyte solution. The XRD and ICP analysis performed for samples obtained from the electrolysis confirmed that the resulting antimony ingot has an exceptionally high purity.

Investigation of synergistic effects using alkanolamines on post-synthetic modification of metal-organic framework and CO2 adsorption capacity

The net global carbon balance is a key modern and even existential environmental issue to humans. Therefore, developing highly efficient gas separation technologies, e.g. based on the application of solid adsorbents, is critically important. Among the advanced solid adsorbents metal-organic frameworks (MOFs), especially MIL-101(Cr), which offers superior physicochemical properties, have proven to be highly promising porous materials for such purposes. In this approach, MIL-101(Cr) nanoadsorbent was functionalized using four alkanolamines (MIL-101(Cr)-alkanolamine) to enhance its CO2 adsorption capacity by increasing the polarity of its pores. Additionally, the synergistic effects of steric hindrance (-CH3 and –CH2CH2OH) and the basicity strength (pKa) of alkanolamines on post-synthetic modification (PSM) of MIL-101(Cr) were investigated. Alkanolamines were selected as the organic ligands because their nitrogen atoms (amino group) coordinate with the chromium ion in MIL-101(Cr), while the hydroxyl groups increase pore polarity and improve the CO2 adsorption capacity through creating weak hydrogen bonding (H-bonding) interactions, resulting in reduced energy consumption during regeneration. In this study, PXRD, IR, and FE-SEM results demonstrated that the crystal structure and morphology of nanoadsorbents remained intact after modification. CHN and ICP analyses were additionally employed to calculate the Nalkanolamine/Cr ratios. CO2 adsorption capacities of all MIL-101(Cr)-alkanolamine nanoadsorbents (∼30–∼45 %) and their selectivity profile (CO2:CH4 and CO2:N2) exhibited significant improvement as opposed to MIL-101(Cr). Investigations revealed that the adsorption capacities of all nanoadsorbents negligibly changed after five adsorption-desorption cycles.

On controllability of fluidized bed reduction of iron ore by CH4 for selective formation of magnetite

Magnetization roasting technology is one of the most representative ways to improve the magnetic separation efficiency and iron recovery of refractory weakly magnetic iron ores. However, utilization of CO-rich or H2-rich gas of strong reducibility as reducing agent for magnetization roasting would lead to over-reduction of Fe2O3 in the ore to non-magnetic FeO, which makes the magnetism of the roasted ore be lower than its maximum, and hence leads to a lower iron recovery than expected. To explore the possibility of using CH4 as reducing agent for controllable reduction of Fe2O3 in iron ores to selectively forming magnetic Fe3O4, i.e., for maximizing the magnetism of the reduced ore for efficient iron separation and recovery, a series of fluidized bed reduction tests in CH4 were carried out on two iron ores of 55 % and 33 % iron at different temperatures for different periods of time, and the resultant reduced ore particles were magnetically separated for recovery of iron concentrate. XRD and ICP analyses were performed on all recovered iron concentrates to identify the crystal forms of their iron species and to quantify their iron contents. The results have shown that the controllable reduction by CH4 of Fe2O3 in the iron ores to strongly magnetic Fe3O4 can be realized by controlling the reduction temperature and time condition applied. The resultant concentrates can be fully recovered by magnetic separation in a weak magnetic field of 60 kA/m to attain a maximum iron recovery of 98 % for the high-grade ore and that of 65 % for the low-grade ore. Besides, the results have also shown that the most critical factor affecting the controllability of the ore reduction process and the selectivity to the generation of magnetic Fe3O4-containing particles is the reduction temperature, and that the upper temperature threshold for the controllable reduction and selective generation of strongly magnetic iron concentrate is about 650℃.

Leachate analysis of trace metals from e-waste disposed of in landfills and open dumps

Waste electrical and electronic equipment (WEEE, or e-waste) has been largely generated worldwide, but the estimated proportion of WEEE that undergoes the correct disposal is very low. The objective of this study was to evaluate e-waste trace metals in the leachate from disposal of WEEE in soil, using different analytical approaches to determine how these methods may interfere in the results. Different forms of WEEE and MSW landfilling and open dumping were simulated in column reactors to analyse the resultant leachates. Analyses of heavy metals in the leachates were performed in two ways: via inductively coupled plasma-mass-spectrometry with acid digestion of samples, following American Standard 3015A, and via inductively coupled plasma-optical emission spectrometry without acid digestion (US Environmental Protection Agency - USEPA, 2007). Metal concentrations found in the landfill and dumping simulations were similar, but a higher concentration of metals was found in samples with e-waste content, and those undergoing acid digestion prior to ICP analyses. Exceptions were Ba e Zn with a higher concentration without digestion, what may indicate the appearance of matrix effect. Concentrations of Pb, Cu and Mn in the leachates indicate possible interference with MSW. Additionally, it was evident that the timescale of observation influenced the results.

Short channeled Zr-SBA-15 supporting copper-based nanoparticles: synthesis, characterization, and antibacterial activity

Antibiotic resistance and the high infectivity of bacteria pose an increasingly threat to human health. Mesoporous silica supporting metal-based nanoparticles are considered an effective strategy to fight bacterial infections. In this work, the short channeled mesoporous Zr-SBA-15 (SBA-S) material is synthesized by sol-gel method using ZrOCl2·8H2O as an additive. Nanoparticles based on four types of copper species, Cu, Cu2O, CuO, and CuSO4, are successfully prepared, forming the Cu-loaded SBA-S materials. The composite structures are comprehensively characterized by SEM, TEM, XRD, XPS, UV–Vis DRS, FTIR, ICP, TG, and BET analysis. It turns out that all structures maintain the arrays of highly ordered pore channels, high specific surface area (SSA, ≥500 m2 g−1), and narrow width of pore size (∼7 nm). The release of Cu2+ ions shows the order is CuSO4/SBA-S > CuO/SBA-S > Cu2O/SBA-S > Cu/SBA-S. Antibacterial activity assay indicates that CuO/SBA-S shows 1.25 and 0.62 mg mL−1 of the minimum bactericidal concentration (MBC) values against E. coli and S. aureus. The acting mechanism would include the free Cu2+ ions and the nanoparticle-induced reactive oxygen species (ROS). We propose that the cheap CuO/SBA-S material would be a promising antibacterial agent with the good antibacterial activity.

Chinese Echoes

This paper presents a single artefact, a base sherd from a storage jar. The pot is dark grey stoneware with a thick, light grey-green celadon glaze. The inside is slipcovered with a thin layer of beige-brown clay and has distinct turning marks. Theoriginal theory was that this might be Chinese Dusun Ware, a type of storage jars which were widely exported from East Asia to the Middle East during the 8th–10th Centuries CE. Such an artefact would have been sensational to find as far north asOslo, Norway, although the sturdy pots were widely reused and have been known to travel to North-Western Europe. To check its provenance, ICP analyses were carried out – and thus a completely different story could be written, one of Western Europeans copying the much sought-after East Asian pottery in the Late Medieval and Renaissance periods. So how did this convincing Chinese copy arrive in Oslo, who could have brought it, and when did it arrive on these shores? Importantly, what can a Chinese copy tell us about relations and connections between Europe and China? We were intrigued, and wonder how many other examples of this may be found in the Nordic countries?